SERS-active nanocellulose substrate via in-situ photochemical synthesis.

Surface-enhanced Raman scattering spectroscopy (SERS) is a highly-sensitive technology to detect trace target analytes. Herein, a series of flexible SERS substrate for the detection of malachite green (MG) bactericide were developed via in situ photochemical synthesis of silver nanoparticles (AgNPs) based on two dimentional (2D) nanocellulose film without additional reducing agent. For the first time, silver nanocubes (AgNCs) with sharp edges and corners, which are conductive to the formation of hot spots, were successfully prepared and uniformly loaded on the nanocellulose film by controlling the reaction conditions. The obtained composite SERS substrate showed high sensitivity to Rhodamine 6G (R6G) and MG with limit of detection (LOD) of 4.7 × 10-12 and 1.2 × 10-8 g/L, respectively. In addition, the relative standard deviation (RSD) was calculated lower than 15 %, demonstrating the good detection reproducibility. The nanocellulose-based 2D SERS substrate shows the potential as a detection platform in the rapid and sensitive identification of various toxic and harmful pollutants.